That is correct. This vehicle officially called ISU-152V was a Finnish captured ISU-152 assault gun modified as towing vehicle. Summer of 1944 Finnish Army captured two of these armoured vehicles and one of them (which had been damaged in fighting) was modified to this kind of towing vehicle. As you mentioned later its 152-mm howitzer was re-attached and now this vehicle on display in Armour Museum located in Parola. What I understand this vehicle was intended as a heavy salvage vehicle (for salvaging other damaged armoured vehicles), but calling it artillery tractor is close enough. The particular document could be called "design plan" or "concept drawing". I found it among "Armour Office" documents (of Finnish Armed Forces GHQ) in one of my visits to Finnish military archives (Sota-arkisto). While the later photographs of the actual vehicle reveal that all the details were not exactly like in this drawing it does list all the modifications needed to be made for the vehicle. The document also calls it KV-JS, which suggests that Finnish military may not have known the exact name of the vehicle that the Soviets were using at that time. Attached is bit larger version of this photo showing also the texts that were in it.Steady wrote:Artillery tractor made from a JSU-152 tank? This vehicle is now in Parola armor museum, its gun reattached.
Texts with translations:
KV-JS:n muuttaminen traktoriksi = Modification of KV-JS as a tractor (towing vehicle)
Luonnos = draft
Vetolaitteen tulee soveltua sekä yhdellä että kahdella tangolla vetämiseen = The towing equipment must be suitable for towing with both one and two bars
Muutostyöt = modifications
1. 152 mm tykki poistetaan = removal of 152-mm gun
2. Eteen ja perään vetolaitteet = Towing equipment to front and back
3. Ajajan luukku suurennetaan = Enlargening of drivers hatch
4. Vaunuun asennetaan 20 mm it.ase = The vehicle will be armed with 20-mm anti-aircraft weapon (*)
5. Moottoriin tehdään äänenvaimennin jonka putket johdetaan maahan = Engine will be equipped with a muffler and the exhaust pipes will be lead toward the ground
6. Hinauksessa tarvittavat varusteet y.m. sijoitetaan = Correct places with be prepared for the equipment needed for the towing and other materials
(*) (in the end it got armed with 20-mm L-39 antitank rifle).
Over to you Steady.