I'm thinking long bolts will hurt you more than help you. The lip on the firewall necessitates a pretty steep angle to get the trans past it, and I've had good luck putting a jack and a block of wood under the crank pulley to tilt the engine back just a hair. If you do end up wanting some guide bolts, I'd get the trans real close and past that lip, and then install them just to guide the last 3/4" or so. The biggest hurdle is the input shaft and the disc, and thats where the alignment tool makes life easy. I've had mine in/out more times than I care to admit, and never had much issue lining it up, as long as you have a clutch tool to line up the disc. DO NOT install bolts and use them to "draw down" the bell housing to the block. It'll slide into place with a solid thud and be fine, then you can install the bolts.