Are you saying that you have a flat tappet cam that's already been broken in? That's the only way I'd consider ever running one again, and I'm a cheap basturd.
If you have a Pull-A-Part near you, go find a Vortec Suburban (less likely to be abused) and pull the cam, lifters, pushrods, spider, dogbones, cam retainer plate, and distributor gear. If your block doesn't have roller cam provisions, you can use the spider as a template to drill and tap the oil gallery in the center of the lifter valley and install all-thread. If you don't have the cam retainer bolt holes you'll have to run a cam button. You should be well under $100 all-in, and the L31 cam has better specs than the TBI cam.
If you're really froggy, you can get a set of Elgin 1.6 rockers for about $170 and make the L31 cam into something decent. My math says around .445" lift. I have a $150 350 I'm midway through rebuilding with this setup.
Elgin, Long Slot Steel Rockers, Chev SB (87-Up), 3/8 1.6BR Chev SB (87-Up), 3/8 1.6, Self AligningBR Stamped from high strength steel alloy, specially heat treated and designed to resist rocker arm flex. Long slot design to handle high lift profile cams. Each kit includes special grooved rocker...
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