Using a solenoid-type battery isolator as a heavy-duty relay?

I'm in the process of installing a air "system" in my Chev Silverado and have decided to use the large Ironman compressor I've been carrying around in the Landcruiser for several years. It is still practically new as I've always had good service from the "Air-On-Board" belt-driven compressor under the bonnet.

However, I want to hard-wire this compressor up to the bank of 3 batteries in the back of the Chev and attach it (via a 3 foot stainless steel braided hose) to a 18 litre receiver tank.

The sticker on the side of the compressor says it draws 45 amps, so I can't use a regular 40 amp relay.

Instead, what I've decided to do is use a 100amp battery isolator solenoid and a 60 amp manually re-settable circuit breaker. The solenoid will be activated by a wire connected to the tail lights.....the Chev's lights come on automatically every time I start her up, although there is the ability to then turn them off if I wanted to. That would mean that whenever the engine is started the compressor will ensure the tank is full to 100 psi. I have installed a 70/on ...100/off pressure switch as well as a safety blow-off valve, so it's all good and safe.



So, the only thing I'm not 100% sure of is whether the 100amp solenoid would be okay to act as a large relay.....as far as I know they do the same job.

Thanks in advance.

Roachie