Too Much HEAT!!!

1991 XJ-6

I'm a new member (this year) of Jaguar Drivers Club of LI. Looking forward to car shows!!!

Need some advice - please

1. My 1991 XJ-6 - purchased new. In the summer - TREMENDOUS amount of heat comes in by my feet when car is warmed up and driving. Took to Jag dealer who said it was a small solenoid operated door in the heater box that was not closing. To replace the solenoid - some crazy amount like $1300 because dash had to be taken off.
Question - is there an easy way to get to this door and just screw or wire it shut for the summer season? Hate to spend that much on this, but it does get hot in there.

2. Recommend please a good factory shop manual for this car and where to buy it.

3. Recommend a bolt-on front brake replacement kit for high performance brakes - cross cut and drilled rotors and new calipers.

Thanks to all!!!!
Regards,
Bill Behrbom