not the full answer .
I have the TF pan on my Source heads and use Andy's batwings seals tight as .
The TF pan is quite thick and I believe it will sit under the TF270 raised port , should only need a bead of sealant .
I would try sliding it in from the front if your heads are on

Tex


New best ET 10.259@129.65 .
New best MPH 130.32
Finally fitted a solid cam,
stepped it up a bit more
3690lbs through the mufflers
New World block 3780lbs 10.278@130.80 . Wowser 10.253@130.24 footbraking from 1500rpm
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