Well I never - I never knew there was a Cromwell Tulip.Cromwell fitted with 'Tulip' Rockets, tested but not used operationally apparently. Looks like aircraft launch rails slung from frames.
Photo from here Panzerserra Bunker- Military Scale Models in 1/35 scale about three quarters of the way down. Note the link in the text to an article on the rocket equipped Sherman.
Paging @Simmerit ....