Electrical gremlins

If you replaced a fusible link with a fuse, that would be the first thing to change back; but it will have to be the correct size for all the new loads.
I love relays, and use them wherever I can, and I use all the same kind, so they are swappable.
Now to answer why she is blowing the fuse; IDK.
But I hope you are not running an electric fan through the bulkhead connector and I hope it is running on an automatic controller.
The ignition should also be on a relay, as should be the EFI.And anything else that pulls more than a couple of amps.Like a fuel-pump....
But I'm pretty sure that you probably already wouldof done all that............