I'd still be worried that a 30 year old NOS shell could be hiding a bit of rot somewhere. There are many tales of shells in primer stored in the rain before finding their way to the production line. Theoretically your shell came for free.....
A firm in Hampshire was restoring an original TR8 about 20 years ago when I visited them. It had spent its life in Nevada and had zero rust although the interior had been severely sun damaged. Inside the sills, arches and turrets were 100% perfect.
Adam
TR7 V8 DHC Jaguar Solent Blue. 9.35cr Range Rover V8, Holley 390cfm, JWR Dual Port, 214 Cam, Lumention, Tubular Manifolds, Single Pipe Exh, 3.08 Rear, 200lb Spax & PolyBushes, Anti- Dive, Capri Vented Discs & Calipers, Braided Hoses, 4 Speed Rear Cylinders, Uprated Master Cylinder & Servo, AT 5 Spokes and Cruise Lights. No Door Stickers. Mine since July 1986, V8 from 1991