preamp design

Where can i get a preamp for a Leslie 825 speaker?
i came across a speaker for free and i want use it because i know it can sound really good. i know it was designed for a hammond organ but i’m hoping i can find some kind of an adapter so i can pay guitar thru it. the back of the cabinet has the nine prong jack. the preamp i that goes to it is a footswitch i think.
What you need is a Leslie “combo preamp”. It is a two channel pre-amp built into a footswitch to let you hook up a 1/4″ instrument cable to the 825.
Here’s the details –
http://www.captain-foldback.com/Leslie_sub/combo_preamps.htm
Here’s a current replacement part –
http://www.trekii.com/UC1A.html
A bit expensive – but might be cheaper than an original , and definitely more reliable.