and here i take mine to the car wash and use the high pressure sprayer on it!

first off you get it wet but it is a cranking issue.
ok, so also you burnt a relay.
i want you in neutral to jumper the battery to the starter,
with a half decent gauge cable, 4Ga car jumper cables work ok.

now how good is the cranking? you might just have a bad/loose power cable, but if you did the selenoid then you probably already checked the rest of the circuit.

under the left side cover you can also jumper the selenoid with a wrench or pliers.

after that, take a spark plug out of each cyl. and try again.

i usually after hosing her down good (in high pressure wash bay), sinse changing the intake, and loosing the fuel pump. have to choke it, and hold my hand over the intake to get it to fire up and it takes a good minute or so (once i get it going to keep it running) before she wont stall out.