Rescaling question

[PNOTNR@aol.com]

List,

I'm working on a 4'10" Lagonda Grand, (Jesse French) originally built in 1929.
This instrument is to be used a high school.  It is a pretty tinny sounding
instrument.

I bought Tremaine Parson's PSCALE program, and put all the information in and
came up with a pretty nice _looking_ scale.  (This is my first venture into
rescaling)  My concern at the moment is that the program calculated the
original scale tension at 38,643 lbs. and the scale I worked out was
calculated at 40,332 lbs.  My two questions, (no doubt I'll think of more)
are:

1.) Is this acceptable?

2.) How do you figure what a plate and frame can take?

Many many thanks in advance for any help

Gordon Large, RPT
Mt. Vernon, ME