I know this is an old post but hoping for some other 124 owners to provide their insight. I bought the trunk lid poppers for my 2019 124 Abarth and have had some issues.
Initially I found the black plastic wedge was too thick to go behind the hinge so I provided some measurements and Sergey sent me some thinner wedges. Having fitted them I've found that the trunk lid doesn't lift up as it struggles to get through the first 3-4 inches of lift. In discussions with Sergey I've measured the force to lift the trunk lid the first 4 inches as 3.8kg/8.4lbs using a luggage scale (https://www.amazon.com/gp/product/B00A8SXGKA) which is much higher than for a MX-5/Miata.
So the questions are:
1) are all 124s seeing the higher force required and hence the trunk popper springs are not working
2) are just 2019 124s seeing some sort of revision in the trunk area that is causing the higher force required
3) is it just my 124 that is seeing the higher force being required.
Even if you don't have the trunk lid poppers, if you are able to measure the force to lift the lid the first 4" with a luggage scale it would be helpful, although please also post your model year of car.
Sergey is being very responsive and helpful so there is no criticism of him, just trying to find out whether this does or will affect other 124 owners as well