Ok great, haven't read Final Exit yet, but here are 3 different takes in full details. Can't get more sweaty :
* Oregon : 20g + 20g Chloral hydrate + 3(-6g) Morphine Sulfate + 30ml Ethanol / 3ml water + 4-6h fast + stat 20mg Meto + 8mg Zofran + 30-60ml alcohol/non-acidic
* Guide : 10g + 300mg Diazepam/Flurazepam (long) (+150mg Midazolam (very short)) + 36h AE
* PPH : 10g + Sodium carbonate + 1g Dilantin + ? Oxazepam/Nitrazepam (intermediate) + alcohol + stat/regimen AE
Oregon remarks theirs can burn, not only bitter
Definitely less straight-forward than N, plus possible to get confused if tempted about arrangements not understanding which component does what
Speaking of Oregon, regarding the duration, the official data (2001-2019, I've verified that the max extreme happened after 2008, so no overlap) backs the Guide (2006), stating it can take max 3 days, more pessimistic than the 24-36 hours OP presented, in worst case scenarios