Get yourself some 70 jets, they are small threaded brass pill looking things with a metered hole in the middle, about 7 bucks nowadays at a speed shop, fewer bucks on line. They have a screw driver relief in them so you can screw 'em in like a threaded insert. Get yourself a small bowl to catch some gas in. Remove the front bowl of the cold carb, lower corner screw first, itll be the hole that all the gas runs out of, just put your bowl under there (whatever side has more clearance) and unscrew the bowl bolt, The bowl is about 1/2 filled with gas so lots will pour out. remove the rest and catch the smallll bit of gas thats left when you break the bowl seal. The jets will be screwed into the plate between the bowl and the body. the block may try and come off too so hold it against the body when you break the bowl seal, you ll save yourself a gasket. Youll see the 2 brass jets right there on the lower 1/4 of the metering block. Unscrew them and screw the 70's in. If bowl gasket came off clean in one piece, your lucky. If it tore, clean off and get yourself a new one. Most chain parts stores have them in blue, (bring the remains of your old one to match up, there are about 4 different bowl gaskets that Holley used) they are the good ones anyway. Put bowl back on, but remember to put the Acc. pump lever under the spring loaded pump actuator, EZ to forget. They sell bowls that have access ports to make jet changing EZ-r but All they seem to do is make you buy the special jet driver and save you a 1 doller gasket.
