What clutch are you using on your early 273

I use one from a slant 6 B-series van with added springs. Had a local clutch builder make it up for me.
The Clutch Masters shop here went out of business. That's too bad. He could beef up anything and it would work perfect. I think the B&B clutches sold have 9 springs with room for 12. The guy said he could add 3 more and match the ones in there or replace all 9 (or 12) with heavier ones for more clamping force. He could also reline the disc with semi metallic, ceramic or kevlar.