[concours] E-type - Question on Authentic Jaguar Competition Mods

I plan to slalom the 1967 E-type. I would prefer to show it in its slalom
configuration when I get to that point, but IN Class C5, not in Class 16.
It will be slalomed in Class D (unmodified 6 cyl E-types).

The preferred show and go configuration would be:

painted 5" front wheels and painted 6" rear wheels (Jaguar P/N C.18922).
According to my owner’s manual, the preferred tire for each of these wheels
are 6.00X15 tires for the front and 6.50X15 tires for the rears. Racing
tires all round. Radials (it’d be silly to race on bias ply tires when the
car is late enough to be fully reconfigured from the factory for radials).

My questions are thus:

Will I be subject to mismatch deductions when the car is equipped as
recommended in my Jaguar Owner’s Manual?

When the car is configured as above, what should the spare be?

                                          -Steve A.

'67 E Type Coupe
'76 XJ6C
'91 XJ40