According to the caption on p.167 of Karl-Heinz Munch's big "653" Album, they apparently got 2 turretless D model Panthers as recovery vehicles during the mid 1943 Kursk battles (they were for pushing and pulling only, not having a winch or spade like the regular Bergepanther).
They later appear in Spring 1944 (I'm assuming the same two) - one with a Panzer IV turret, the other with a quad 20mm Flak mounted above its turret ring.
On p.371 theres a shot of the Pz.IV version on a flatcar, and on p.377 it is seen again traversing a ditch - very difficult to see if its wearing a turret no. like the artwork you linked to shows (but its possible), though it does sport a cross on the turret skirt and the round 653 logo on the front lower LHS corner of the glacis plate.
The caption states that "The Panzer IV turret with the 75mm gun was bolted to the chassis and immobile. The driver had to point the entire vehicle in the direction of fire." This seems a little odd to me as it would make it virtually useless as an offensive AT weapon without any traverse at all other than via the driver - unless for H&I fire only, but I guess hes obviously got some annecdotal evidence for this claim to have printed it...
On p.381 theres another shot of the second Panther D and the caption states that "The maintenance company mounted a 20mm quadruple anti-aircraft gun on this vehicle in June 1944." Sadly theres no shot of it in this format - has anyone ever seen one?
In the text on p.320 theres a listing of unit strength as at July 1, 1944 and this quad Flak equipped Panther is included under the vehicles in "Combat Staff; Detachment Commander", though oddly in this list theres no mention of the Pz.IV turreted Panther, unless its concealed in one of the company's maintenance sections?
In the text on the same page the mix of these oddball vehicles (ie. these 2 Panthers, 1 VK.45.01, 1 T-34 with a quad 20mm, and 2 turretless T-34 ammo carriers), are mentioned as being the work of 653's master armourer - Stabsfeldwebel Anton Brunnthaler around May/June 1944 with permission from the CO; Major Gillenberger. (Of note too is the fact that in June '44, 653 also got 4 Elefants with unique hinged split rear doors in place of the standard bolted one piece job).
On p.200 there is a shot of another turretless D on a flatcar though supposedly from s.Pz.Jg.Abt.656 between August 26 and September 1, with something high under a tarp in the turret ring area - WAG time - maybe another field mounted Flak gun possibly a 20 or 37mm?? Who knows...