ABS core dash pads are a complete replacement, not a cap. Molding ABS less expensive than stamping a metal core. Of course, the fit is terrible and durability is even worse. ABS does not like the temperatures an interior can reach in summer, so ABS cores are very prone to warpage, with E-bodies and '71-'74 B-bodies being worst-case scenarios. Plan on replacing one within a few years. The steel reproductions don't warp, but the jury on how Asian vinyl lasts over time is still out, and the fit is dicey. With the complexity and expense of E-body dash pads, it's not something you'll want to visit twice.
Year One doesn't "go through" anyone. They sell the above Asian reproductions after getting out of the reupholstering business many years ago. When they did recondition pads, they did not use Just Dashes. YO's were done on the original Chrysler tooling by an outfit in Texas with the same type of machinery the original vendor used. Year One owned the factory tooling. They were, by a long shot, the best on the market.
Year One's pads were stripped down to the bare metal frame, leaving none of the original foam behind. 100% new foam was injection-molded onto the frame via the original process. As shown on their websites, Just Dashes and Legendary actually leave as much of the original, split and rotting foam in place and simply fill between with new. It's how they've always done it. They charge a lot for this service, possibly because it's far more labor-intensive than the original process, with reasonable results. The general hobby opinion of JD and Legendary pads is they're not as crisp in detail and look too "puffy", at least on the E-bodies.
This was something on which I spent months, with Kev's help, to make sure I got the best dash available for my dream car. Asking on E-body sites, direct comparisons of samples at shows, the whole shebang. The best option out there, bar none, is ABC Moparts. His pads are stripped bare, with no original deteriorating foam reused. When I received mine, I compared it to a nearly-flawless original pad that came with my car (but had the wrong speaker count). The injection "tails" were identical in location and size, and other minor flaws present in the OE pad were present in the restored one. ABC has Year One's old tooling. While he will not tell you this, that means it's the OEM tooling. He also has the same company doing the work that Year One did.
As a bonus, ABC's superior pad is much less expensive than either Just Dashes or Legendary. Give Bob a call; he's a great guy both in conversation and business. He'll treat you right--he even sent me a box (I paid the shipping for it, of course) because I couldn't find one big enough for my dash pad. You will need to ship him your core as he appears to be out. He's my go-to for dash pads now, meaning even the lowly '68 Valiant's dash pad is going to him. It's worth it.
If you're shipping out your pad to be restored: Make sure you remove the VIN plate before you do. Do not attempt to drill the rivets; grind them off from behind so they won't spin and scar your VIN tag.
If you're wondering why Year One stopped restoring dash pads: Despite multiple printed warnings and verbal reminders during ordering about not sending the VIN with the dash pad, people were too stupid to listen and sent pads with VINs on them. It was (and remains) a violation of Federal law for them to remove and/or return it. There were E-body pads stacked like cordwood when I was there, several being U and V codes. By law, we were supposed to destroy them but couldn't bring ourselves to do it, so there were a couple of pallets' worth of pad cores lying around for years.