If this were me, I'd find a proper torque wrench, fire the engine and run it for ten--fifteen minutes. Shut off the engine, let it cool, and re-torque the heads. I don't see any point to tearing it apart when the bolts are likely "close" as-is.

If "peace-of-mind" is important, well, do what you gotta do. For the record, SBC headbolts are reusable. There's no need to buy another set. Other, newer engine families use torque-to-yield head bolts but the SBC is old enough to use decent hardware.

What sealer did you use on the bolt threads? That may be the important difference--if the sealer is entirely set-up, retorquing may just disturb the sealer and create seepage.

 

I am fairly certain the newer 1/2" head Vortec bolts are TTY and use TTY torque method. I actually broke one trying to reuse them about 10 years ago. Since then I have always used new bolts on Vortecs. I always replace them with aftermarket non-torque to yeild bolts and use the standard torque method to the spec of the bolts. Usually 75 ft/lbs. My last 3 engines have had Jegs brand bolts. Work great for me. I have reused two sets multiple times. FWIW I never retorque them either. Would be too much of a pain in the *** in a Van especially my Express van.

 

I actually lucked out and used the 3/8 drive. the bolts had stretched. i rechecked with digital torque adapter was within 1.5-2 ftlbs of each other. did the other head as well. put rockers and pushrods in

 

motor is in and have it running decent but since it's gotten warmer the temps rise in idle. drilled 2 holes in 180*stat- no bad spike at warmup. swapped in another fan clutch- temps still reach 194 in traffic and drive thru. just ordered a 4 row aluminum radiator-https://www.alloyworksplus.com/produ...57l-v8-91-1993 hopefully this will help since the 305 had a 1 row. was running 89 octane during fall, winter and spring. now running 93 to avoid ping-may be temp related

 

My '97 C/K service manual for 305/350 says nothing about TTY. In fact, two of the steps for reassembly are to clean the bolt threads, and apply fresh sealer to the (re-used) head bolts. The head bolts on my Lumina are the same--Torque-Angle but not TTY. The Lumina service manual specifically says that the bolts can be re-used if they're in good condition.

Be aware that TTY is a variation of Torque-Angle fastener tightening. Torque-Angle tightening does not require yielding the bolt. TTY is just Torque-Angle that spins the head enough to permanently deform the fastener.

Torque-Angle tends to be more precise than just torquing to a higher torque value.