In the QUAD (that is, first series, after the QUAD.12 and before the
QUAD II) promo/operating booklet, it is categorically stated that
Acoustical did "all metal work, finishing" etc in-house under the
supervision of the AID department (whatever that may be). In Britain
at this time, and well beyond the Quad II period, any manufacturer who
didn't want to lose his reputation took very great care of metal
preparation. (For instance, one of the bugbears of Rolls-Royce and
Bentley of this period is mu-metal pitting on door handles and other
brightwork one handles, ugly --and rough on fine pigskin gloves -- and
not capable of refinishing to the standard required for successful
rechroming.)



If one can afford to restore a Rolls to RR standards one can afford
to restore it better-which means having those parts filled and molds
made to make steel investment castings of them. In fact I think there
is a place selling a kit of them already done fairly reasonably.

Another substantial upgrade is the use of Oldsmobile valves in the RR
V8 engine.