Any good auto parts store will have the "helicoil" style. They are sold under numerous brand names, but are all the same thing. They are the thick black inserts. The kit comes with the tap, inserts, and the tool to set them in place.

Use lots of cutting fluid, and use a shop vac right next to the drill/tap to catch any loose shavings. Anything left should burn out the exhaust since its an aluminum head.

88 4R, 350 V8, R150 5 speed Sold <...uot; />
97 4R, stock, daily driver
98 Sienna, kid and dog hauler, wife's ride