Billy's "backup" guitar for Gish, used on all of the Gish solos. In an entry on Kerry Brown's blog from 2009/10/20, he says this about it:

I bought this guitar around 1989 or 1990 because I needed a spare for playing live, and wanted an almost identical sound to go with my main one at the time which was an early 70's Strat (yellow that I hand painted). THAT guitar was the featured guitar on Gish and was probably my favourite guitar ever. It was stolen in 1992 out the back door of St. Andrews Hall in Detroit and has never resurfaced. I would still pay good $ to get that guitar back, no questions asked. So THIS guitar is the last remnant of that period of my life, and I really cherish it. It was painted ala Eric Clapton's cream era guitar by my friend crazy Nick. As you can see it's taken a bit of a beating back from a time when I used to throw my guitars around like candy. The history of this guitar is its a 1978 'bullet' Strat with the flat pickups (as opposed to the staggered pole pieces). I preferred these pickups at that time because it allowed for maximum gain by running the pickups up really close to the strings. This guitar does have some recording history of note, as it was the guitar I would use for solos as it seemed to just have more cut than the main one. So all the solos on Gish were done with this guitar. It has a vicious attack as you can hear on songs like 'Tristessa', 'I Am One', 'Rhinocerous', and 'Siva'. I'm fixing this guitar up now and I hope to use it again soon. I've started using more old-school amplification, like my 1969 Marshall Super Tremolo head (currently ailing) so guitars with this kind of cut are what I'm looking for. It makes me laugh that I'm sort of back to where I started when it comes to gain and attack. I see the BC Dimarzio pickups as more the modern application of gain, and the older type pickups as a more vintage approach to the use of gain.

In a later facebook entry, also cross-posted to Kerry's blog on 2010/12/23, Billy offered a $20,000 reward for the return of his stolen Gish guitar.