How thick to build up Marine Tex in hole?

Got my grey Marine Tex ordered, will be here tomorrow. I did find the 14 oz size on iBoats. Since our hole is completely thru keel cap, and VTBob had mentioned build up of Marine Tex from outside and inside, we're wondering if we can do the whole thickness at one time, or split it up so its not taking so long to cure? And do we just stuff the hole full until its coming out the top side? With no backing behind it, not sure of proper procedure? And we've found a few more small holes in hull, one right next to a rivet, and one that was patched with some kind of red tipped hardened stick looking patch, it's very hard. Looks like one of the melting sticks you'd use with a torch they've described on here. Can we touch up these places with the Marine Tex and then hit with Gluv It inside and out? (As long as they're cleaned properly first.) Some previous owner had used small globs of JB Weld and Bill got that off with heat gun and scaper. Otherwise we wouldn't have known some of these existed. We're thinking after we patch it with Marine Tex, let that cure, then Gluv It, let that cure, we should put some water in boat again and recheck for leaks. Is that right, or should we check before Gluv It is applied.? I sure hope all this works, my husband is so discouraged, he just wants to scrap it. But I believe it will work, and besides we can't afford to do that, then we'd be boatless for sure. Thanks