battery fuse keeps blowing when trying to crank

[180fan]

Car: 89 240sx with an s13 SR20DET

Background:So I've recently finished my rebuild and moved my battery to my trunk. Using 2 awg wiring, I've hooked up my battery in the trunk to a 100A ANL fuse that finishes the connection to a distribution block (splits from 2awg to two 4 awg) that splits off to the starter and the constant that came off as two plugs that goes to the + terminal. At the part where the constant comes off, I've built a small box that gives power to the electric fans as well. At the battery, I've also got a 1 farad capacitor just before my amp.

Problem:When I try starting the motor, the 100A fuse blew out that I've got running to the distribution block. When the key is in any other position, all the electronics works fine. The fuse only blows out when I try to crank the motor.

Tried:I've checked the starter, and the power doesn't seem to be grounding to anything. I've checked the alternator and found that the plastic part that's keeping the power from grounding out is still there. When there's more light, I'll check if it's cracked but doesn't appear to be.

I've also pulled the fuse that runs to the cap to see if the cap was putting too much draw on the battery.

Plea:Any other things I should check before giving it another try and possibly blowing out another fuse? I have now bought 120A fuses but would like to see if there could be anything else I overlooked before putting in a bigger fuse and possibly overlooking a bigger mistake.