Hi, hopefully the pictures and links will explain this simple mod. It takes about 10 minutes excluding glue drying time. The springs bought are 16mm od, 8mm id and 50mm long if you want to use washers or 55mm if you dont. They need to compress by about about a third (ie from 55mm down to 35mm). The washers are 16mm od, 8mm id, 2mm thick. My Gas struts could support the boot open but were worn so I replaced them anyway.
Here are the links I used:
Heavy Load Duty Compression Die Spring, 8-18mm Diameter & Up To 55mm Long JIS
https://www.ebay.co.uk/itm/223584768462?hash=item340eb0d1ce:g:5O0AAOSwLxBdKLk7
2X TAILGATE BOOT GAS STRUTS FOR SKODA OCTAVIA MK2 COMBI 04-13 ESTATE 1Z9827550
https://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=2+x+tailgate+boot+gas+struts+for+skoda+octavia+mk2+combi+04+13+estate+1+z+9827550&_blrs=spell_check
Metric M8 plastic washers 8mm ID 16mm OD 2mm pack of four
https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313&_nkw=Metric+M8+plastic+washers+8mm+ID+16mm+OD+2mm+pack+of+four&_sacat=0
20210512_164832.mp4