Very nice! I thought about doing larger flanges (like CSP) for better bolt clearance, but wanted to keep it a "standard" size. The jig will help keep everything were it should be from the heat of welding. Give your friend a "practice part" to see if he can do it or not. Welding thick to thin material can be tricky for the novice. I like to help everyone out in some way... posting "how to do it" is one of them.
BTW, my header is STILL NOT DONE
but I'm trying to get the time. Almost done with a conversion to one of my power tools to aid in header builds. Will have something to post soon.
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1970 T1 W/MassIVe 2913cc RAT/?EFI? w/direct fire (very soon) and 915 trans
1962 SC 1776cc SP 944NA brakes, 993 wheels
VKG