My '31 with a TCI Stage 3 IFS I have just enough room (1/2" to spare) under the '32 grille splash shield to get a little 2 ton jack and a specially made block to the front cross member. Both wheels are then raised. I haven't tried it with a flat tire, but think I have a problem. The rear - again a bit tight with the 4 bar and the '32 gas tank getting to the differential to jack. And with a flat tire - an oh s@#t.

This is the front - it's actually about 5.25" now after some coil over adjustments:

And the back before the weight of the body dropped it a bit more:


Mine's a full fendered roadster so even going under the sides takes a 'plan'