Well it took almost 4 years but I may have found an answer for you about the MF 135 Stilt tractor.
Turns out their is still one surviver in the UK. Here is what I learned in an email with Pictures of it.
Hi, I recently saw one of your posts online by John Farnworth regarding a Massey Ferguson 35 stilts tractor as you call them, at the end of the post he says quote, I wonder if any of these tractors still exist in the UK, well in answer to your post there are as I have one, this one is a 1973 135 version made by Lenfield Engineering from Maidstone Kent, sadly they don’t exist anymore, it was one of two that a company I worked for called Chalk Valley Contracting in the south of England, I first drove this machine at the age of 19, I know that the other one was scrapped and mine was sold to a farm for spraying Christmas trees, it too was destined for the scrap heap but through a series of coincidences I was able to approach the farming company to sell it, I believe Lenfield built 10 of these called flamingo conversions based on both 35’s and 135’s, I also came across a photo of the first one built in which the frame was slightly different, there seems to be no other examples left so mine could be the last example remaining, if this is of any interest to you or your friends I would be happy to send some photo’s yours sincerely, Tim
please find photos of my Massey 135 flamingo, the first two pictures are mine at a local show here in Dorset, the next is at home on the first drive after I had rebuilt it, my goal was to drive it to the local show three miles away bearing in mind the last time I drove it I was 20 when I put it back together I was 50! and it seemed a lot less safe at that age The next photo is of an earlier model based on a Massey 35x probably about 1964 This is the similar frame design to mine Next is a photo sent to me by a friend, this we think is the first model built as it is based on a 35 with a standard 4cylinder engine with a down swept exhaust, also the frame is different as the chain drive boxes are inverted and inboard to the frame, it may be the proto type to this model, the picture is at the Royal Kent Show I believe, I have pictures of mine when I used it in anger, it had 24foot sprayer boom and front and rear tanks fitted, we had two of them at Chalk Valley Contracting the other one was scrapped, these stilt tractors originally had blower booms fitted and went around Dorset, Wiltshire and Hampshire dusting field Beans, also we used to do ultra-low volume spraying for mildew on cereal crops, finally mine was sold when we got a new modern sprayer based on a Fendt tool carrier, it ended up spraying Christmas trees then was assigned to the scrap heap, where I retrieved it at a cost more than the scrap value!
I will look out for the pictures of it when spraying and of the scrap pile when I found it Hope this is of interest to you and your MCA members and follower Kind regards