Interior/boot separation

[Pabarlow]

Hi, new Elan coupe (s3 DHC) owner here, though not new to Lotus cars. Like many, I'm dealing with terrible exhaust fumes in the interior.
I'm working on the boot / trunk lid seal and fit. I've read the post suggesting sealing the interior from the boot with glued-in plastic. And I will consider tail pipe position options. I'm sure I'll resolve this via those avenues of exploration.
But, it makes me wonder, does anyone ever fully seal off the interior with fibreglass (or maybe fibreboard and figreglass, like a series 2 Europa)? It seems like a vertical panel, plus horizontal panel under the rear "parcel shelf (?)" under the rear window, all glassed in, would make for a lovely cozy interior.
I understand maintaining access to the rear diff mounts, strut mounts and any body mounts. But it seems like there could be a body stiffening advantage to be gained, as well as ensuring zero access from boot fumes from gas, battery, or exhaust.
Thanks.

[elancoupe]

Assuming no leaks in the system, extending the exhaust tip slightly beyond the rear most point on the body can help. Some aspect of the aero of the rear bodywork causes the exhaust fumes to ?swirl?, witness the numerous Elans that I have seen with soot on the back.

[Frogelan]

Peter

On the S1/S2, the boot area is sealed by a panel (have a look at the photos) which is in front of the diff mounts.

Why not also look very carefully at the front connections of the exhaust?

Andrew