Yes.
Functionally cut the blue coming out of the firewall. Use the firewall end to trigger the relay, feed the relay through a big fuse or breaker off the starter relay, and wire the engine bay end of the blue to the load contact.
You can put an unobtrusive toggle in the relay coil ground and create a simple anti theft. You know how easy it is to hot-wire these girls
View attachment 1715628832
Bulkhead connector end of blue goes to 86, 85 is ground. Don't reverse these as most relays have a spike diode
30 is main power in, from the starter relay "stud"
87 is output to engine bay end of blue. 87A is not used it is normally closed IE closed with relay at rest
Some high current relays are normally open only, and the two terminals are both 87 and not 87A
