A word of advice & caution - unless you want to do rust repairs on the firewall & elsewhere in the engine bay - do not get a cracked tray, nor one of the early ones without the rib.
I'd suggest getting a repro late tray with the stiffening ribs (keeps it from sagging over time due to heat in bay) - either a good condition used with no cracks or bite the bullet for a new repro from Mikey914, AA, etc.
The old early unreinforced trays would sag & sent a waterfall down onto the firewall & heat/sound pad to rust at that location, and a cracked one sends it wherever the crack points it.
Don't save a few bucks to cause $1000s in rust repair! Yeah, I know, AZ is desert, but this is coming up on your monsoon season, so unless your kid will keep it garaged in every rain & never get caught out when one pops up - save yourself the grief!
My 73 had the factory early tray which sagged & the heat pad's sisal filling nicely held the moisture against the firewall to eat thru a row of rust perforations along the wall to engine tray seam.
JM2C!
Tom
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