I would say no. At best it would be extraordinarily difficult, to the point that you would be wondering “why didn’t I just remove the door”
Are you only replacing the “A” pillar rubber, or all the door seals? If the “B” pillar seal as well, you will end up with a door slammer with the seals that’s supplied by most of the parts suppliers. For a start, its not the correct cross section seal that they supply. They all supply a BD20500 section labeled as the correct BD28434.
This wouldn’t be so bad if the seal was made totally out of soft rubber, but the manufacturers, or those that commission the manufacture, trying to punch above their weight in terms of design capability, have them made using two densities of rubber as shown in the following picture…
This seal installed as supplied will require a run up to slam the door hard enough to close.
What many do is cut and remove completely, the section shown between the to two Red lines in the following picture.
This is tantamount to buying a dog and then having to bark for it.
This seal supplied by XK Unlimited, now Moss, used to be like the following, made totally from soft rubber and they worked. However, I was told by a colleague and it was reported by an E Type Club UK Forum Member, that this seal purchased from Moss recently, was the same two density rubber construction as the others.